Method for destruction of organic compounds by co-oxidation with activated carbon

• US 6,982,068 B2
• Filed: 04/29/2003
• Issued: 01/03/2006
• Est. Priority Date: 05/01/2002
• Status: Expired due to Fees

• Current Assignee: AC Fox, Incorporated
• Original Assignee: Hugh Stanley Mclaughlin
• Inventors: McLaughlin, Hugh Stanley
• Primary Examiner(s): NGUYEN, NGOC YEN M
• Application Number:
  US10/425,327
• Publication Number:
  US 20030206848A1
• Time in Patent Office: 980 Days
• Field of Search: 423/245.1, 423/245.3, 502/38, 502/39, 502/40, 502/41, 502/42, 502/51, 210/694
• US Class Current: 423/245.1
• CPC Class Codes: B01D 2253/102 Carbon
• CPC Class Codes: B01D 2257/70 Organic compounds not provided for in groups B01D2257/00 - B01D2257/602
• CPC Class Codes: B01D 2257/708 Volatile organic compounds V.O.C.'s
• CPC Class Codes: B01D 2259/40083 Regeneration of adsorbents in processes other than pressure or temperature swing adsorption
• CPC Class Codes: B01D 53/0438 Cooling or heating systems
• CPC Class Codes: B01D 53/0454 Controlling adsorption controlling temperature swing adsorption B01D53/0462, controlling pressure swing adsorption B01D53/047
• CPC Class Codes: B01D 53/72 Organic compounds not provided for in groups B01D53/48 - B01D53/70, e.g. hydrocarbons
• CPC Class Codes: B01D 53/73 After-treatment of removed components
• CPC Class Codes: B01J 2208/00044 Temperature measurement
• CPC Class Codes: B01J 2208/00407 outside the reactor bed
• CPC Class Codes: B01J 2208/00415 electric resistance heaters
• CPC Class Codes: B01J 8/0278 Feeding reactive fluids for solid material B01J8/0015
• CPC Class Codes: B01J 8/0285 Heating or cooling the reactor for tubular reactors in furnaces B01J8/062

Abstract

A method for oxidizing carbon adsorbable organic compounds in a controlled manner within a bed of activated carbon. The bed of activated carbon is exposed to a source of molecular oxygen, such as air, and is controlled within a temperature range whereby the molecular oxygen is slowly oxidizing the activated carbon. Under this controlled set of conditions, the activated carbon will oxidize organic compounds present within the bed of activated carbon. This technique has widespread versatility for the controlled destruction of organic vapors and liquids by activated carbon and applications for the regeneration of spent activated carbons containing previously adsorbed organic compounds.

Claims

1. A method of oxidizing an organic compound that is adsorbable by activated carbon, the method comprising:

providing a bed of activated carbon;

flowing through the bed a gas comprising a source of oxygen molecules;

heating the bed to an operating temperature range whereby the oxygen is oxidizing the activated carbon, as evidenced by heat generation;

controlling the temperature of the bed within such temperature range; and

flowing through the heated bed a stream comprising an organic compound, resulting in the adsorption and oxidation of the organic compound, and the evolution from the bed of products of the oxidation of the organic compound.

2. The method of claim 1 wherein the heat generation results in local temperature increases of at least 1 degree Celsius as compared to local temperatures present in the absence of the source of molecular oxygen, as created under essentially equivalent operational conditions by no vapor flow or an essentially equivalent flowrate of an essentially oxygen-free vapor stream.

3. The method of claim 1 wherein the upper limit of the temperature range is less than the ignition temperature of the activated carbon, as measured by ASTM D 3466-76:

Standard Test Method for Ignition Temperature of Granular Activated Carbon.

4. The method of claim 1 wherein the temperature range is from about 150°

C. to about 375°

C.

5. The method of claim 1, further comprising adding into the heated bed a source of supplemental liquid water or water vapor, to influence the oxidation reactions occurring within the bed.

6. The method of claim 1 wherein the stream comprises vapors of the organic compound.

7. The method of claim 6 wherein the vapors of the organic compound exhibit an equilibrium weight adsorption on the activated carbon that, is at least as great as that of propane at substantially the same vapor phase concentration at substantially the same temperature.

8. The method of claim 6 wherein the temperature range is from about 190°

C. to about 270°

C.

9. The method of claim 1 wherein the stream comprises a liquid comprising the organic compound.

10. The method of claim 9 wherein the liquid comprising the organic compound exhibits an equilibrium vapor pressure at least as great as that of USP mineral oil within the bed operating temperature range.

11. The method of claim 9 wherein the liquid comprising the organic compound exhibits an equilibrium vapor pressure not more than that of toluene within the bed operating temperature range.

12. The method of claim 9 wherein the temperature range is from about 225°

C. to about 275°

C.